What is High-Definition TV

What is High-Definition TV :

There are a lot of misconceptions, a lot of products, and some scams out there when looking to purchase an HDTV. Being that it is still relatively new to most people, it can be a confusing time, especially when the next gen consoles are going to make you want to purchase an HDTV.

First, an overview of what "HDTV" is:

Traditionally, TV has been broadcast at 480i. This means 480 interlaced. The frame of the picture is scanned every other line down, and then once again every other line up, which then creates the frame for that specific sequence.

There is also "EDTV", which stands for "enhanced definition television". More or less this is 480p, or 480 progressive, which means the entire frame for that particular shot is scanned in one pass, which creates a clearer picture with virtually no flicker. More or less if you see a set advertised as an EDTV, about the most performance you will get out of it is a set that will be able to support an incoming signal from a progressive scan DVD player, or a game console which is able to send a 480p signal.

Enter HDTV, which has a couple different formats. 720p, and 1080i respectively. Right now these are the two formats battling for supremacy in HDTV land. 1080i is the standard used for most stations now, with ABC and ESPN (possibly a couple others) still hanging on to 720p.

When dealing with HDTV sets, they each have their own native display format. This means the signal which it can support as displaying without alteration of that signal via downconverting or upconverting (which I will touch on in a minute) This native display will either be 1080i or 720p. Most, if not all, LCD fixed displays will support 720p natively. Most RPTV's, CRT's - will support 1080i natively.

Here comes the tricky part. A lot of the less expensive sets out there, and even some of the others, will only accept either a 720p signal, or 1080i signal. If it sees a signal come in that it doesn't natively support, the set will downconvert the signal to 480p automatically so it can display the image. For example, you have a 51" Model WS500/510 that displays 1080i as it's native resolution. The program you are trying to view, or the game you are trying to play, is transmitting at 720p. This particular set will see the 720p signal, and downconvert this to 480p. Making this particular set, when receiving anything but 1080i native signals, essentially nothing more than a glorified EDTV.

There are now more and more sets coming out that will finally upconvert. For instance, the 34" Sony CRT tube based HDTV set. If this set sees a 720p signal coming, it will automatically upconvert the signal to 1080i so as to still receive the signal in high-definition. The basis for all this is to make sure that you are purchasing a set which will upconvert 720p to 1080i if you are going with a set that natively supports 1080i, and not downconvert to 480p. This is very important, and should be reflected in your purchase. Especially when games on the Xbox 360 (and other consoles) will be coming in both formats.

So the next big question is determining the right set for you. This all depends on the subjective layout of your home theater, lighting, budget, gaming area, and personal preference. I'll attempt to cover each of the technologies, their plusses and minuses. Most of these will be heavily related to gaming, but will also cover home theater.

An explaination of some terms:

  • Burn in: Static images that, if left on over time, will leave a permanent fixed image on your screen. Examples would be health-bars or the logos of TV channels that're always in the same place.
  • Convergence: Manually targeting a series of points over the screen as a whole to properly align the guns that project a picture on a TV set.
  • Upconvert: Takes an incoming signal and adjusts it so it can still display it in HDTV format.
  • Downconvert: Takes an incoming signal and downgrades it to be viewable by the set. Usually this means it will convert an image out of HDTV and force it into EDTV because it cannot accept a native 720p signal. But recently it also means if it receives a 1080i signal, it can downconvert it to 720p so the TV can still take advantage of the HD source.

Time to look at some of the different types of TV set:

CRT (Cathode Ray Tube) - Traditional tube based TV sets:

Advantages: These sets are terrific for gaming. They require no manual convergence and are pretty much ready to go out of the box (with a few tweaks I will get to later). The picture quality is pretty good, too. Tube based sets are still subject to burn in, but not nearly on a scale as to which Plasma's and RPTV's are. Most sets will upconvert 720p to 1080i, with most CRT's natively supporting 1080i. Contrast ratio and brightness are fabulous, and you can easily adjust the picture depending on the light source without worrying about torching the tubes over an extended period of time. You do not have to worry about dead pixels, or running out of plasma.

Disadvantages: Cost is higher than some other sets. Weight and size also plays a key issue. Some are deeper than normal. For instance, a 34" Sony HDTV clocks in at around 200 pounds. It doesn't seem like much, but with it's bulk makes it almost impossible to try and get into different positions without help of at least two people that lift weights regularly. There is still minor screen burn issues, but nothing to really worry about unless you leave the same static image on for 45 days straight. Expect though to pay about the same price for a 34" CRT HDTV depending on the brand) as you would for a 46-51" RPTV.

LCD (Liquid Crystal Display) TV's:

Advantages: Lightweight, usually a more refined picture. Depending on versatility can usually be used with a PC or set top media center. Screen burn is non existant so static images over time will not hurt the set. You do not have to run a manual convergence. Of course these sets are much smaller in scope, and very easy to carry around if you want to move your set up a lot.

Disadvantages: Most companies require a lot of dead pixels before they will take them back under warranty. Blacks are more grey-ish and are not deep or rich true blacks. Lamp replacement is usually not convered under warranty and will sometimes hit in the $300 dollar price range within 2-4 years. Depending on the set, you can really get screwed if you do not watch for low reaction times. Preferably a 16 Ms reaction time would be good enough for most gamers, but if you are an enthusiast, you may want even lower. Price is still pretty high and when comparing what can happen to an LCD set with the cost, and what is and not covered, you really have to weigh your options. Also watch for contrast ratios and CD/M brightness quality. A lot of sets on the market now and using lower tier OEM LCD screens to hit certain price points. For the most part, cheaper isn't better.

RPTV's (Rear Projection Televisions):

Advantages: Deep rich blacks that almost come close to the level of a CRT based tube TV. Very good color quality. Do not have to worry about dead pixels or plasma charge. High amount of screen display for a relatively lower cost. For instance, a Sony 34" HDTV was the same price as the Sony 51" WS520 rear projection set. Decent vertical viewability. Most parts are readily available, and if you can get a hold of a service manual, you could probably teach yourself how to repair the set. Most of these sets are very cost effective.

Disadvantages: Screen burn is more rampant than traditional tube based sets. Convergence is a must, and you will learn whether you want to or not how to converge these sets on your own. Service level convergence (where you enter the service menu of a set via a set of codes on your remote) is about 60 times better than any auto convergence or manual convergence through a regular menu system. If you move your set, be prepared to reconverge. Also, these things are massive. So if you have limited depth space, you may want to think twice. Analog television doesn't look good either. Very grainy. Games look decent as long as the set is converged. One of the major downfalls is that these sets traditionally accept 1080i native resolution only. And about 95% of them downconvert to 480p. So if you have a game which displays 720p, you are out of luck. Ask your HDTV provider if the set top they will lease you will upconvert 720 to 1080i at the source. Usually these set tops are good at doing this, albeit some loss of quality. These sets have amazing potential, but usually an ISF calibrator is needed to really see the true potential of the RPTV. These guys come to your house and spend upwards of 8-10 hours with various equipment to bring you the best picture possible. They also charge about $500.00. If you get a Best Buy rep selling you a warranty saying it includes a free ISF calibration per year, kick him or her in the genital region, head butt them in the face, and walk out of the store.

DLP (Dynamic Light Projection):

Advantages: These sets are above RPTV's in quality without the hassle of convergence. There is no possibility for screen burn. They are relatively light and thin, and put out an amazing picture. Colors are fantastic, although sometimes blacks have a bit of a problem (supposedly). They are not as bulky as a traditional CRT based set or RPTV, and resemble more of an LCD case look. There can be a bit of a rainbow effect depending on the set you purchase.

Disadvantages: Blacks sometimes have what is called a "Rainbow" effect. Meaning sometimes you can see various colors in a black because of the way DLP works depending on the reflections. Lamp replacement usually every 2-3 years at a cost of around $300.00 or so. As of this point they are pretty expensive over RPTV based sets. One of the biggest limiting factors at the moment is the way games are handled. Now, some sets are immune to this, and others are having some problems. There is sufficient lag being reported from reaction time with the controller, to the set reacting to the image and displaying said image. Some samsung's are being hit hard with this, and they have yet to react to the problem. Some sets even in the same model line up are completely immune and not showing any signs. Most, if not all, of these sets natively support 720p and upconvert to 1080i. Which can be a blessing or not depending on how it goes in the way of HDTV.

Plasma:

Advantages: Great picture display, very nice colors. Better black levels than LCD but still fail a bit in comparison next to a direct view CRT set. These are also very thin and easy to hang on a wall or attach to a mounting rack. Prices have dropped and continue to drop for Plasmas with introduction of other technologies.

Disadvantages: Screen burn susceptibility more so then RPTV's especially in initial setup. Black levels are better than LCD but still pale a bit in comparison to a direct view CRT.

Note: The EDTV trap of Plasmas has all but vanished for the most part. Make sure if you purchase a Plasma you are checking the life of the display overall, and double check to make sure the resolutions aren't off the wall numbers.

Differences between Conposite, S-video, Component, and other sources:

  1. Composite/RCA: This is the worst possible connection you can use. If your set supports S-video, please use it. Composite basically ties every signal into one cable and throws it at the set.

  2. S-video: A huge upgrade from Composite. Basically the color seperation is done within the same cable, but has it's own dedicated line. Hence it looks like a PS/2 mouse adapter plug. Every small wire that connects to the S-video female port (hot) carries it's own signal for richer color seperation and less signal degradation.

  3. Component: If you have a set that has component but does not support progressive scan, the improvement is minimal. You may as well stay with S-video. If you have a set that supports progressive scan however, switch to Component and start using 480p. The difference is amazing. Remember, you cannot display a 480p picture using S-video or composite. Only Component and up.

  4. DVI: A pure digital connection that was designed for copyright protected HD data over cable, sat, etc. It isn't going to be used much anymore unless you are a PC user.

  5. HDMI - A new digital connection that can carry the audio and the video in the same connection. Purely digital - and will most likely take hold in the coming years. You will want your set to have HDMI, if anything because it will free up component inputs.

Monster Cables:

From what I've heard, these are a complete 100% rip off. A decent shielded cable from radio shack for $19.99 perform just as good as a $150.00 monster cable which will radiate nitrous oxide from it's bowels and make you laugh at the infidels using RCA hook ups. Do not let anyone sell you on these things. There are going to be people that swear by this, and for that I will just say it is placebo effect at it's finest. If you spend that amount of money, you will be convinced it looks better just because you paid the extra cash. The only thing you want to concern yourself with is to make sure the cable is shielded to keep out surrounding noise from penetrating the cable when transmitting the signal. Gold plated connections do seem to work a little better with picture quality, but you can find the same gold plated connections for about $5.00 more.

When shopping for an HDTV set:

Basically watch out for sales tricks. After reading this post, when you go into a best buy or circuit city, you'll know more about these sets than the staff there could ever hope to know. Things to look out for:

  1. Make sure the set upconverts 720p to 1080i if the set you purchase natively supports 1080i. Although this is becoming less of a problem being that most set top boxes and consoles will do the upconverting for you, there still may be times when the TV set in question can do it better, or you may have an older set top that doesn't do this for you.
  2. Make sure the set has an HDMI input.
  3. Make sure you have enough component inputs on the set, or purchase a receiver that you can use as a switch.
  4. Warranty plans do not cover ISF calibration.
  5. Do not fall for the EDTV trap. Even though this is declining, some sets appear to be very good deals only to find when you get them home they only accept a 480p signal and are not truly high definition.

Consoles:

The Xbox 360 has been confirmed to be able to upscale games at the source. Therefore, you will not need to have a set which will scale for you. Only ime will tell how many games will come out in 720p native, or 1080i native.

Warranties:

This is kind of a tough one. 7% of people who purchase a warranty actually use them. If you can call the manufacturer to do warranty service, do it. Not a knock on technicians from super stores, but technicians from the mom and pop stores that are authorized by the manufacturer have better service, follow through, and want to see you happy. On a side note, if you can purchase a set from one of these smaller stores, you may pay an additional $100-200 more, but the service you receive for the life of your product will pay for it in the long run.

Just because a set has component input, doesn't mean that the set supports 480p. If you are looking for a lower end set, some can be deceiving. Make sure you verify if a set can support 480 progressive.

Also a quick word on DVD players. There is a new product out there with regard to DVD players that will upconvert a DVD to 1080i or 720p at the source. This will usually require an HDMI connection.

A lot of people are buying into these thinking they will be able to pop in their DVD's and instantly get HD resolution. This couldn't be further from the truth. In actuality, a 480i source (DVD) being upconverted to 720p or 1080i at the DVD player itself and then passed through another cable looks no different in blind tests than a good 480p DVD player. The thing with this is, most of these players are terrible when used through their component outputs. Depending on where you go, HDMI cables can cost a fortune. Even online. Be careful.

A word on Avia and calibration DVD programs:

There are DVD's that you can purchase that come with tinted colored glasses that guide you through a process to get the best picture out of your set for whichever room you have it in. It will go through brightness levels, contrast, tint, color, sharpness, etc - and at the end you will have an optimized picture.

THX DVD's comes with their own optimizer if you do not want to spend extra money on personal calibration. You can run these tests from any normal DVD player and select the THX options from the DVD movie itself.

THX also has a sound test to make sure you have correctly set up your sound system. While not as in depth as something on Avia, you still have enough to work with to make sure your speakers are correctly place.